One reason for the limited number of studies is that it is very difficult to identify wrinkles—even deep ones—in histological sections. When the skin is excised, the wrinkle opens and partially disappears—evidence that the wrinkle is an aspect of the whole skin. To overcome this problem a novel technique was used whereby a line of cyanoacrylate glue, visible in Figure 30.1, was introduced into the wrinkle and allowed to set prior to taking a biopsy of the wrinkle. With this precaution, the shape of the wrinkle was preserved through processing allowing a better correlation of histological changes to the architecture of the wrinkle. Sections of these biopsies, which were taken from the periorbital crow’s feet area were stained by a variety of techni-ques using both conventional and immunostaining techniques.

We confirmed the finding (4,6) that the elastic fiber network was far less damaged at the base of a deep wrinkle than on the sides of the wrinkle or adjacent skin (Fig. 30.1). This is thought to be a consequence of the base of the wrinkle being less exposed to ultraviolet light during and after formation, than the surrounding skin. It suggests that the damage to the elastic fiber network is unlikely to be a primary cause of the wrinkle.

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